• Journal of the Korean earth science society
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• v.32 no.6
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• pp.586-594
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• 2011

Gravity Recovery and Climate Experiment (GRACE), launched in April, 2002, makes it possible to monitor Earth's mass redistribution with its time-varying gravity observation. GRACE provides monthly gravity solutions as coefficients of spherical harmonics, and thus ones need to convert the gravity spectrum to gravity grids (or mass grids) via the spherical harmonics. GRACE gravity solutions, however, include spatial alias error as well as noise, which requires to suppress in order to enhance signal to noise ratio. In this study, we present the GRACE data processing procedures and introduce some applications of time-varying gravity, which are studies of terrestrial water storage changes, Antarctic and Greenland ice melting, and sea level rise. Satellite missions such as GRACE will continue up to early 2020, and they are expected to be an essential resource to understand the global climate changes.

• Survey Research
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• v.5 no.2
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• pp.31-48
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• 2004

We collected and analyzed 18 social surveys to assess the quality of samples with respect to region, gender, age-band, education level and occupation. We found in our samples that highly educated people and house wives are over-represented whereas low educated people, self-employed/blue collars and white collars are under-represented. To correct such sample distortions, we applied the iterative proportional weighting or the raking to our samples. We observed sizable changes in survey results. Also, the effective sample sizes were shrunken up to 20%-40%, that could be interpreted as the necessity of larger samples to meet the claimed sampling error limits.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.21 no.2
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• pp.111-127
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• 2010

This study aims for developing an instructional design strategy to improve collaborative teaching between teacher librarians and subject teachers in library-assisted instruction. Collaborative teaching is an important management activity enhancing teaching role of teacher librarians in their school community. But in the actual condition the level of the library-assisted instruction as its practical strategy is cooperation and subject teachers are leading teaching and learning except for selecting resources. Because library-assisted instruction is resource-based learning, the procedural knowledge of information literacy curricula and topics of subject specific curricula should be designed as a whole. Also, there must be possibilities of reducing trial and error and expanding successes. From these sides, the collaborative design strategy for library-assisted instruction can be planned like 'statement of learning situation-co designing-co teaching-co evaluating'.

• Survey Research
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• v.11 no.2
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• pp.161-176
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• 2010

The purpose of this study is to evaluate the opinion survey data quality used in theses and to suggest the data quality evaluation model. We used 16 items which were suggested by KASR(Korean Association for Survey Research) as a standard of survey data quality evaluation in thesis. According to the result, the data quality used in the theses is very poor level not to be accepted. And we tried difference tests between two proportions in order to find there were significant differences among stochastical variables. The result showed that there were some significant differences in sampling error and number of analyzing method between doctor and master. we suggested a model that was weighted by 9 special items for a survey data quality evaluation in a thesis by observing them from KASR's principles.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.4
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• pp.137-143
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• 2010

This paper deals with the performance comparison of self adaptive equalizer by the weighting factor of MCMA cost function for the compensate the amplitude and phase distortion which occurs in the communication channel. The MCMA is improves the cost function of present CMA at the output of equalizer for the minimize of error function in the amplitude and phase, the value of weighting factor is used at this time. When the comparison of equalizer performance, we classified to initial state and steady state, then it represents the convergence time and convergence speed and steady state operation of equalizer to the predetermined level, it is determined by the weighting factor. We confirm to the different result to this 2 state by weighting factor values using computer simulation. By using the result of this paper, if we appropriately choose the weighting factor values in the environment of communication channel, it is expected that the high quality digital transmission is possible.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.11
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• pp.61-68
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• 2004

Today almost all chips have IEEE 1149.1 tap controller inside. Recently the circuit is embedded in the chips for other functional objectives. Hence a CED technique for testing and monitoring the IEEE 1149.1 tap controller had been proposed. This paper studies the optimal CED test technique on the IEEE 1149.1 tap controller. There are duplication, parity prediction, and hybrid techniques. The hybrid technique shows the best result on the area overhead. This means that the hybrid technique is perfectly adequate for the IEEE 1149.1 tap controller to be applied to test with the optimal area overhead and can be used widely in the field. Furthermore, we made more reduction from the previous method resulting in less area overhead.

• International Commerce and Information Review
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• v.19 no.2
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• pp.65-84
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• 2017

This paper attempts to investigate FDI Trade have been viewed a power affecting economic growth in Mongolia and five Central Asian countries(Kazakhstan, Uzbekistan, Kyrgyzstan, Kazakhstan and Turkmenistan) directly and indirectly using the Vector Error Correction Model. The results of empirical analysis based on data from 1995 to 2015 confirmed that FDI had a significant impact on economic growth in the rest of countries expect Kazakhstan and Turkmenistan, and Trade was not statistically significant for all countries. Accordingly we've come to below conclusion in consideration of the results of the statistics survey. It is urgently required to implement the policies on promoting foreign investment at first in order to recover economic decline though the international trading is considered important in developing the economics of developing countries. Especially, the landlocked countries, namely the countries having same border should focus on promoting the development of transport and freight forwarding systems between the countries, implementing the policies on trade relationships and foreign direct investments throughout the nation in consideration of the low- level of market economic conditions.

• Korean Journal of Child Studies
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• v.6 no.1
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• pp.17-40
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• 1985

This study investigated Korean children's early acquisition of negatives and focused on four research questions: 1) processing of negative variations; 2) the nature of negatives when negatives are completely acquired in Korean (in which meaning and form are matched in one to one mapping); 3) the validity of Bellugi's negative acquisition model in Korean; and 4) the cause of child's erroneous sentence production: limited ability or regularity in children's cognition. The language data of the five subjects (age span; 1.1 - 3.11) were collected by their parents in the natural setting of the home. The results showed that 1) the pivot form, was processed in many ways from a simple to a complicated form, such as <(X+X')+N> <(x+x')+N,Y> <(x+x') N,(y+y')>. It appeared that the children used a simple negative format to reach a one-step advanced negative format. 2) Korean negatives are divided into range of negation in the negative sentence (part or whole), strength of negation (absolute or general), functions of meaning (negation, absences, refusal, prohibition, impossibility). All five children acquired negative sentences in all functions and the complete range after 3 years of age. 3) In spite of the differences in age level, Bellugi's four stage model was in evidence; that is, Korean children's negative acquisition was almost identical with Bellugi's tour stage model in deep structure. 4) Analyses of children's error sentences showed that the sentences with errors were made not because of the children's limitation in cognitive ability but because of the strict application of regularity of rules from the original grammars. Consequently, the children produced negative sentences using two rules: the rule of additive complexity (from simple to complex) and the rule of division (from one to several).

• The KIPS Transactions:PartB
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• v.13B no.5 s.108
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• pp.553-560
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• 2006

Speech recognition has recently been investigated to produce more reliable recognition results in a noisy environment, by integrating diverse sources of information into the result derivation-level or producing new results through post-processing the prior recognition results. In this paper we propose a method which uses the user's usage patterns and the context information in speech command recognition for personal mobile devices to improve the recognition accuracy in a noisy environment. Sequential usage (or speech) patterns prior to the current command spoken are used to adjust the base recognition results. For the context information, we use the relevance between the current function of the device in use and the spoken command. Our experiment results show that the proposed method achieves about 50% of error correction rate over the base recognition system. It demonstrates the feasibility of the proposed method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.1A
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• pp.9-17
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• 2004

Adapt ive and fixed step size PC (power control) schemes for accommodating voice, video, and data are evaluated according to the different PC command rates and their effects on integrated Voice/Video/Data are investigated. The required minimum power levels are derived as PC thresholds and the effects of PC errors on channel quality and radio 1 ink capacity are investigated. The services with high bit rates and low bit error rates can cause a significant effect on the radio link qualifies of the other types of traffic. The results show that the adapt ive step size PC scheme for voice/video/data services can achieve more capacity and cause less interference to the radio channels because less minimum PIL(Power Increment Level) is required for the specified radio link outage probability.